BMW E21 E30 325 2.5 12V M20B25

Exhaust valve steel serie-black set for BMW E21 - E30 325 2.5 12v motor M20B25, year 1977-1992
The price is for unit (each). 

The SUPERTECH valves manufactured by a very exhaustive process of precision, the CNC material is machined in several steps, heat treatment and hardening treatment with nitride, once these processes are finished, a Supertech patented treatment of "superfinish" is applied. , finished to eliminate all imperfection and impurities.

As main characteristics of these valves we can highlight:
- excellent quality in all its materials.
- high resistance to fatigue
- extra durability and performance.
- hardening + 52HRc
- Very strict tolerances in terms of finishing precision.
- Excellent proportion heat dissipation.

Available according to models in various types of materials.
Sodium. These valves are filled with sodium inside, with a very significant reduction in temperature in the head and a weight reduction of 10%. Ideal for turbocharged engines with high operating temperatures.
Black series. Admission valves made of high quality EV8 steel (21-4N) and EV16 steel exhaust valves (21-8N), designed to withstand high loads of exhaust temperatures, with special hardening in the seats and the tip of the shank.
Inconel. Made with an aluminum, steel and nickel alloy, ultra reinforced for exhaust valves mainly, ideal for engines that reach high working temperatures. It provides a better distribution of heat throughout the valve, reducing the temperature of the head remarkably.
Titanium. Made in a forged titanium alloy, very light in weight and very resistant.
Designed for very professional engines that rotate at very high revolutions.

Consult measurements in EXTRA INFO

Specifications: 
Materials available:
- steel black.
- inconel 
Ø head: 36,00mm - 37,00mm (+1)
Ø stem: 6,95mm
Length: 102,50mm